Punishing Poverty

Our Board of “Education” has engineered a reporting system
that rewards the more affluent divisions and penalizes the poorer ones.

We have seen that economically disadvantaged (“ED”) students underperform their more affluent peers (“Not ED”) in terms of pass rates on the SOL tests.  In 2018, that underperformance ranged from 17.43% on the History & Social Science tests to 21.82% on the writing tests.

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This places schools and divisions with larger ED populations at an unfair disadvantage with respect to the SOL averages.

Here, to start, is a selection of reading pass rates.

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I’ve selected these nine divisions because their ED populations are spaced at about 10% intervals.  (They are, from the left, Falls Church, Powhatan, Arlington, Gloucester, Bath, Dickenson, Roanoke City, Northampton, and Greensville.)  The orange diamonds are the division average reading pass rates of the Not ED students; the green triangles are the ED pass rates. 

The SOL average pass rates are the blue circles.  The divisions with smaller numbers of ED students to drag down that average have higher SOL numbers.  Indeed, the divisions with fewer than 51% ED (the statewide average) enjoy a boost; divisions with more than 51% suffer a penalty.

The extreme examples are Falls Church and Greensville County (which includes Emporia).

Falls Church had the lowest ED numbers in the state, 9%.  The reading pass rate for their Not ED students was 95%; for ED, it was 67% (a 28 point spread; no bragging rights there).  The average of the ED and Not ED averages was 81%, which would have been a fair measure of the performance of both groups.  The division SOL pass rate, however, was 92% because of the small number of EDs.  Falls Church thus enjoyed an eleven point SOL bonus for affluence.

Greensville County was the other end of the scale, 93% ED.  The pass rates were lower: 76% for Not ED, 59% for ED, a seventeen point spread with a 68% average.  But the reported SOL was 61%.  Greensville suffered a 7 point SOL penalty for poverty.

For a more complete view of the situation, here is a graph of division pass rates, Not ED, ED, and SOL, all plotted v. the ED percentage.

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The Falls Church points are enlarged and filled with purple; Greensville, maroon; Richmond, gold.

Let’s simplify the picture by looking just at the least squares fitted lines:

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The statistics of the fitted lines tell three different stories:

  • ED: The fitted line shows an 0.43% decrease in the ED pass rate for a 10% increase in the ED population but the correlation is minuscule.
  • Not ED: The slope is minus 1.35% for a 10% increase in ED and there is something of a correlation.  It looks like increasing the ED population is mildly related to a decrease in the Not ED rate, but not so much the ED (this kind of data can’t show whether the ED population increase causes part of the Not ED pass rate decrease).
  • The SOL pass rate decreases by 2.77% for a 10% increase in the ED population.  Thirty-five percent is a pretty good correlation and the reason is obvious: Divisions with larger ED populations have more ED (i.e., lower) pass rates included in the average.

The math data tell much the same story.

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Here the average of the Falls Church ED/Not ED pass rates is 74% but the small ED population results in an SOL pass rate 13 points higher.  The Greensville SOL reflects a 3 point penalty vs. the ED/Not ED average, which is that small only because the ED and Not ED rates are only seven points apart.

Notice that the Falls Church ED rate again is far below the Not ED, here by 33%, which is double the state average difference.  Either those Falls Church schools are coasting with unusually bright Not ED students, or struggling with unusually low-performing ED students, or doing a poor teaching job with the ED group, or some combination of such factors.

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The slopes again show how the SOL average penalizes divisions with large ED populations.  As well, the R-squared for the Not ED group suggests, even more strongly than in the reading data, that increasing the ED population is associated with an effect on the performance of the Not ED group.

We cannot infer from the data why the Board of “Education” would embrace this system that punishes poverty.  We can notice, however, that the system is unfair on its face. 

Indeed, the Board had a fair measure of learning, the SGP, that was independent of poverty.  But the Board abandoned that system on the flimsy excuse that it could not calculate the results until Summer School results were in.  In fact, they knew that when the started calculating the SGP.  As well, they were (and are) perfectly capable of calculating the SGPs in May for the students (and teachers) not involved in Summer School.  Waiting until August merely gives them a chance to camouflage some of the poor performances during the regular school year.

Your tax dollars at “work.”

Here, for the record, is a list of the divisions that received more than a 2% reading SOL boost from the ED/Not ED average in 2018:

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And here are those that enjoyed a penalty of 2% or more:

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Ah, well, we can make one inference:  If you’re that Board and you’re going to make an enemy, better the Superintendent in Greensville or Colonial Beach than the one in Falls Church or Loudoun.